Centering-mold.



" UNi siArEs JAcoB is vBLAW,A ory PrrrsBUae, PENNSYLVANIA, AssieNoR ooLLAPsiBLE STEEL cENTEEiNe COMPANY, or PiTTsBURe, PENN- sYL-VANIA, A coRPonATioN or NEW JEiisEr.

-oENTEniNG-MOLD.'

Specication of Letters Patent.

Patented May 21,4 i907,

Application led Noireinber v12, 1906. Serial No. 343,009.

To cL-'ZZ whom Wtv may concern:

.Be it known that 1 JACOB B. BLAW, a citizen of the United States, residing at Pittsburg, county of Allegheny, in theState of Pennsylvania, have invented certain new and 'useful improvements in' Centering-` Molds, of lwhich l the following is -a specification.

My invent-ion relates to molds for use in oonstructing concrete se\4\-ers,-conduits, and similar passages, and particularly to the `outer forming portion or sheathing.' The invention has for its objects to provide a sheath adapted to be used with a collapsible mold, which she'ath may be easily handled and securely held in position from the inner mold to promold. V

Figure 2 is a side view, and Figure 31s a section on theline lII--III of Fig. 1.

""-5' Heretofore when sewers or conduits were constructed from concrete, diiiiculty has been experienced in securing the proper thickness of material over the inner form, due to the tendency ofthe concrete to {iow downwardly, and 'furthermore dilliculty was experienced in packing the concrete iirmly about the inner mold. to overcome these diliiculties and provide a light and inexpensive means which can be used repeatedly for positively coniining the concrete and thus securing the proper thickness of material over the inner'mold and allowing the packing and working crete into a Jfirm mass.

Referring to the drawing, I have shown in end elevation a collapsible inner mold suitable for forming largo sewers together with my improved sheath for confining the concrete about the inner collapsible mold. The inner collapsible mold may be ofl any ini- My device is designed l collapse the `inner mold member.

ot' the con-.--

` proved forni, but as shown it consists of four sheet metal plates numbered 1, 2, 3, and 4,

suitably secured together by the overlapping angles 5 together with the loops` 6 and wedges asis common in the art, and also by the4 angles 7, 7. This mold member is stift'- ened by the .braces or turnbuckles 7, S, 9, 10, 11, and 12,securedto the angles 5, 13, and 14, and adapted when 'contracted to loosen the. mold member from the concrete. The member is provided with wheels 16 at its lower edges for riding upon the track 17 when the nioldis contracted, which track members 17 are securedA to the framing 1S.

adjacent the timbers 19. This framing and track is supported on the concrete floor pre,-

viously laid and indicated 20 in the drawing.

Spaced away from the inner mold member is the sheathing comprising in the present case four thin metal sheets 20, 21,' 22,V and 23,

by the dotted lines detachably secured together at the sides by means of the buttstraps Z-l and the loop and wedge construction heretofore referred to, and at the top by means of the-cross rod 25. and clanipingnuts 26. 'The sheathing is secured to the inner mold member by' means of a plurality oi joining members 27 which in the present inst-ance are wires which pass through the sheathing at their outer ends and through thev plates oi' the inner mold member at their inner ends. In .order to reinforce the slieathing'plates at the point of supportci the wire, the small angle sections 2S are provided through which t-he `Wire passes. 4The wire may be secured to the plates of the inner mold members in a number of different ways but is preferably engaged by simply passing through the plate at .one point and back through the plate at a point slightly removed thereby providing a loop, which can he easily cut from the inside when the concrete has set and it is desired to In freeing the shea-thing, it is ot course necessary either to cutI the wire adjacent the membersiS or in ease the ends have simply been twisted together at this point to untwist them. It is obvious that 4other temporary or releasable holding means than the wires might be sub-4 stituted, it only being necessary that such means be releasable both from the sheathing and from the inner moldmember. In using 'the device the plates. zo and 23' will Ordinarily be-rstapplied outside the inner mold memberwhichhas previously "been placed in position, andthe sp'ace between the inner mold member and theplates and 2,3 filled with concrete, lafter .j which gthe" upper sheathing members 21' and'f22@can be secured 'to the lower members'20' and 23 and the remaining concrete necessaryiilled in at the open space adjacent the cross rods 25. After the concrete vhas set the Wires 27.'.are released-rorrrl the sheathing and from the inner mold mem; ber, -atterwhichther` inner mold member may be ycollapsed andmoved along' to a new position, and the sheathing removedl by detach-` ing the connectingrods 25 and then removing the plates 21, 22, 2,0,.and 23. l."

. Figures 2 and 3`4 illustrate the 'manner rin which the sections `20e-21 are joined at thel edge to each other along their vertical edges.`

- and' press against the plates. lThis gives a secure fastening to the edges and makes a tight joint preventing the escape of any of the concrete.. The plates may be stiiiened longitudinally if desired, by means of angles 32, and the upper edges ofthe plates 21 and 22 additionallybraeed from. the inner mold members by means ofstruts'33 (Figure 1).' It will be apparentthat the T-bars. add

greatly to therigidity. of the sheathing, and might under somecircumstances suiiciently support the structure to permit of the disuse of the wires v27,.'and on the other hand other forms rof joints'might be readily substituted for the T joint, and that am not limited to the use of this particular ljoint.A Itlwill be seen from the foregoing that'the thickness of the'cement over thelinnermold .member is positively controlled. by the sheathing and that the material may be packed in between It will also lne lapparent', that because of the holding melnbe'rs 27 the sheathing can be held in proper position even thou h this be of very light and ilimsy material, tus permit- .the'mold and-sheath to any desired extent.

ting of an easily-handled and/inexpensive.A

sheath.. The number of sections'used inthe sheath is of course not limited to four,- anda greater or lessy might be used,`depending upcn vthe conditions of the work.

Having', thus described myinvent'ion' and illustrated its use, 'whatl claim as new and desire to secure by Letters Patent, is the following: i 1. 5'

1. lyncombination in a mold, a collaplsible inner mold,- a thin flexible outer s eath spaced therefrom, vand detachable means connecting the mold and the sheath for sup'- porting such sheath.

v2. ln .combination in a mold., a collapsible inner mold, 'a thin flexible outer sheath spaced therefrom, and a' plurality of wires connectingthe .mold and sheath for holding the sheath in position.l f

3. In combination in a mold, a' collapsible U shaped mold., alarger U shaped sheath of thin ilexible'material thereover and open at the top, and detachable means connecting the mold and sheath for holding the sheathi'n position.A v v j 4. In combination in a mold'7 a thin ilexible sheath composed of a plurality of` vertical strips, joining and stifl'ening means for the adjacent edges comprising a T-bar having'it's flange provided with slots and lyingl between the plates, and wedges for engaging the lslots and bearing against the plates.

- In'testimony whereof, I hereunto sign mv name in-thexpresence'of the two subscribed Witnesses;

` JACOB B. BLAW.

Witnesses:

- J. C. BRADLEY,

ARCHWORTH MARTIN. 

